Black Box inventor dies

[Ed Burke]

ABC news Australia

The Australian inventor of the black box, which records flight data and is integral to crash investigations, has died at the age of 85.

Dr David Warren was principal research scientist at the Defence Science and Technology Organisation's Aeronautical Research Laboratories in Melbourne from 1952 to 1983.

According to the Department of Defence, he investigated the crash of the world's first jet airliner in 1953.

He then advocated voice recorders be used in the cockpit, designing and constructing the world's first black box prototype - the ARL - in 1956.

Australian authorities mandated black boxes be installed in cockpits 10 years later.

Black boxes are now installed in passenger airlines and other forms of transport around the world.

Dr Warren and his team received the Lawrence Hargraves award in 2001 for their pioneering work.

He was also appointed an Officer in the General Division of the Order of Australia in 2002 and had a Qantas Airbus A380 named after him in 2008.

Dr Warren is survived by his wife Ruth, four children and seven grandchildren.

[Tom Goodrick]

That was certainly a significant accomplishment - both scientific and political. The political aspect was that airlines did not want anybody to know how bad things were when their pretty plane broke. There was considerable resistance to publication of crash data. But it was a good thing sensible people won the fight. The crash of TWA Flight 800 over Long Island was a case where the public was able to download the data. I had many files of it. It ruled out a missile strike.

On the scientific side I would wonder how effective those early black boxes were because of the fragility of the media. I began working with flight data acquisition systems in the early 1970's. I found out how difficult it was. At that time we used tape to record the data. Most of my stuff was thrown out of airplanes and had to survive, at the least, a firm arrival under a parachute. Of course we had even greater interest in the data when the parachute did not open. Our technicians spent many hours unkinking mangled tape. In the '80's they started using hard drives and then they switched to memory chips which are actually pretty sturdy, even when the circuit boards get crunched. (Unfortunately, I fractured a couple of chips.)

On my last few parachute tests in the late 1980's, I had a data-logging computer running on a 9v battery in a 3x7x2 inch plastic box. We put that in a 3ftx6inch "bomb" carried first under a 14ft radio-controlled twin engine aircraft and then under a 12 ft parachute. We could record the airspeed, vertical speed and accelerations (as the parachute opened). I would program the data logger from my desktop "PC" (in 1988) to record certain parameters after a trigger signal at certain rates. It's code included a "go to sleep" command to power down when the vertical rate went to exactly zero for 10 seconds. (I neglected to consider swinging from a tree!) I would pick up the bomb, press a button assuring it was asleep, and take it back to the office where I could examine the data.

I had assisted with the design of that twin-engine aircraft so it was with great interest that I read the aircraft flight data for the first few flights. I had discovered just how significant was the relation between elevator angle and airspeed. At low speed the chamnge in angle per ft/sec is high. At hign speed it becomes very low and the design of the elevator/stabilizer and pitch trim device become extremely important. The parachutes tested wre my own unique design that gave low opening shocks and a trade between stability and descent rate based on rigging.